MACROMEDIA FLASH 8-USING FLASH Use Manual page 28

Some problems might occur if you work with only one FLA file and do not save versions
during the process of creating the file. It is possible that files might bloat in size because of the
history that's saved in the FLA file or that a file might become corrupt (as with any software
you use) while you are working on it. If any of these unfortunate events occur, you have other
versions of your file to use if you save multiple versions throughout your development.
You might also encounter problems when you create an application. Perhaps you made a series
of changes to the file and you do not want to use these changes. Or you might delete parts of
the file that you want to use later in your development. If you save multiple versions while
developing, you have an earlier version available if you need to revert.
There are several options that you can use to save a file: Save, Save As, and Save and Compact.
When you save a file, Flash does not analyze all the data before creating an optimized version
of the document. Instead, the changes you make to the document are appended to the end of
the FLA file's data, which shortens the time it takes to save the document. When you select
Save As and type a new name for the file, Flash writes a new and optimized version of the file,
which results in a smaller file size. When you select Save and Compact, Flash creates a new
optimized file and deletes the original file.
When you select Save and Compact, you cannot undo any changes you made before
you saved the file. If you select Save when working with a document, you can undo
changes made prior to that save point. Because Save and Compact deletes the earlier
version of the file and replaces it with the optimized version, you cannot undo earlier
changes.
Remember to use Save As frequently and to type a new file name for your document after
every milestone in your project if you are not using version control software to create backups
of your FLA file. If you encounter major problems while working on the document, you have
an earlier version to use instead of losing everything.
There are many software packages that let users use version control with their files, which
enables teams to work efficiently and reduce errors (such as overwriting files or working on
old versions of a document). Popular version control software programs include CVS,
Subversion, and SourceSafe. As with other documents, you can use these programs to organize
the Flash documents outside Flash.
28 Working with Flash Documents